diff options
| author | Emmanuel Grumbach <emmanuel.grumbach@intel.com> | 2020-11-04 16:46:41 +0300 |
|---|---|---|
| committer | Johannes Berg <johannes.berg@intel.com> | 2020-12-11 14:47:17 +0300 |
| commit | 14486c82612a177cb910980c70ba900827ca0894 (patch) | |
| tree | bce8d66f6a6159acbf7b7fe45b1d609fe4d99ba8 /include/uapi/linux/rfkill.h | |
| parent | 91163f82143630a9629a8bf0227d49173697c69c (diff) | |
| download | linux-14486c82612a177cb910980c70ba900827ca0894.tar.xz | |
rfkill: add a reason to the HW rfkill state
The WLAN device may exist yet not be usable. This can happen
when the WLAN device is controllable by both the host and
some platform internal component.
We need some arbritration that is vendor specific, but when
the device is not available for the host, we need to reflect
this state towards the user space.
Add a reason field to the rfkill object (and event) so that
userspace can know why the device is in rfkill: because some
other platform component currently owns the device, or
because the actual hw rfkill signal is asserted.
Capable userspace can now determine the reason for the rfkill
and possibly do some negotiation on a side band channel using
a proprietary protocol to gain ownership on the device in case
the device is owned by some other component. When the host
gains ownership on the device, the kernel can remove the
RFKILL_HARD_BLOCK_NOT_OWNER reason and the hw rfkill state
will be off. Then, the userspace can bring the device up and
start normal operation.
The rfkill_event structure is enlarged to include the additional
byte, it is now 9 bytes long. Old user space will ask to read
only 8 bytes so that the kernel can know not to feed them with
more data. When the user space writes 8 bytes, new kernels will
just read what is present in the file descriptor. This new byte
is read only from the userspace standpoint anyway.
If a new user space uses an old kernel, it'll ask to read 9 bytes
but will get only 8, and it'll know that it didn't get the new
state. When it'll write 9 bytes, the kernel will again ignore
this new byte which is read only from the userspace standpoint.
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Link: https://lore.kernel.org/r/20201104134641.28816-1-emmanuel.grumbach@intel.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Diffstat (limited to 'include/uapi/linux/rfkill.h')
| -rw-r--r-- | include/uapi/linux/rfkill.h | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/include/uapi/linux/rfkill.h b/include/uapi/linux/rfkill.h index 2e00dcebebd0..03e8af87b364 100644 --- a/include/uapi/linux/rfkill.h +++ b/include/uapi/linux/rfkill.h @@ -70,12 +70,24 @@ enum rfkill_operation { }; /** + * enum rfkill_hard_block_reasons - hard block reasons + * @RFKILL_HARD_BLOCK_SIGNAL: the hardware rfkill signal is active + * @RFKILL_HARD_BLOCK_NOT_OWNER: the NIC is not owned by the host + */ +enum rfkill_hard_block_reasons { + RFKILL_HARD_BLOCK_SIGNAL = 1 << 0, + RFKILL_HARD_BLOCK_NOT_OWNER = 1 << 1, +}; + +/** * struct rfkill_event - events for userspace on /dev/rfkill * @idx: index of dev rfkill * @type: type of the rfkill struct * @op: operation code * @hard: hard state (0/1) * @soft: soft state (0/1) + * @hard_block_reasons: valid if hard is set. One or several reasons from + * &enum rfkill_hard_block_reasons. * * Structure used for userspace communication on /dev/rfkill, * used for events from the kernel and control to the kernel. @@ -84,7 +96,9 @@ struct rfkill_event { __u32 idx; __u8 type; __u8 op; - __u8 soft, hard; + __u8 soft; + __u8 hard; + __u8 hard_block_reasons; } __attribute__((packed)); /* |